Question

33) A beaver eats the inner bark of an aspen tree and converts the potential energy in this bark into the kinetic energy of building a lodge (in the form of a river dam) complete with an underwater entrance! This example illustrates:

A) How energy can be destroyed and created

B) That all energy transformations lead to an increase in local disorder

C) How every energy transformation decreases the entropy of the universe

D) That beavers are energy transformers

E) How all of the chemical energy from the beaver’s food was lost as heat

34) Which is most accurate? A spontaneous process:

A) Occurs quickly

B) Concentrates energy

C) Increases order

D) Is energetically favorable

E) Has a positive ΔG

35) With respect to the overall reaction for cellular respiration:

A) The chemical products of respiration are of lower free energy than the reactants

B) This is an endergonic reaction

C) Energy to make ATP is obtained directly from the sun

D) This reaction absorbs free energy from its surroundings

E) Kinetic energy is released from the bonds of sugar molecules

7 of 9

36) Which is NOT an example of cellular work that can be accomplished by ATP?

A) Pumping of ions across a membrane by the Na+/K+ pump

B) Transport of a vesicle along a cytoskeletal track

C) Movement of water across a membrane via osmosis

D) Synthesis of a complex protein from amino acids

37) What is true with respect to ATP hydrolysis?

A) It yields water and a molecule of inorganic phosphate

B) It yields products that are less stable than the original reactants

C) The electron transport chain is key in releasing energy from this reaction

D) It can drive forward an endergonic process

E) It stores energy as it loses a phosphate group

38) The initial investment of energy for starting a reaction is called the:

A) Transition energy

B) Catalyst energy

C) Activation energy

D) Reactant energy

E) Barrier energy

Answer 1

33. ANS: B. That all energy transformations lead to an increase in local disorder

When the beaver cuts down trees and their dams flood riparian forests, some species of trees decrease in abundance while others increase

34. ANS: C. Increases order.

A spontaneous reaction is not necessarily a quick reaction; it could proceed very slowly. The second law of thermodynamics states that a process involving an isolated system will be spontaneous if the entropy of the system increases over time.

35. ANS: A) The chemical products of respiration are of lower free energy than the reactants.

Cellular respiration is a set of metabolic reactions and processes that take place in the cells of organisms to convert biochemical energy from nutrients into adenosine triphosphate (ATP), and then release waste products.

36. ANS: C. Movement of water across a membrane via osmosis.

Osmosis is the process in which a solvent moves from a solution of low concentration to a solution of higher concentration

37. ANS: B) It yields products that are less stable than the original reactants

38. ANS: C. Activation Energy

The initial investment of energy for starting a reaction or the energy required to contort the reactant molecules so the bonds can break is called Activation Energy.